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Purpose: Human T-lymphotropic virus (HTLV), cytomegalovirus (CMV), and Epstein-Barr virus (EBV) each have the propensity for infection as well as the development of latency in humans. As many ocular tissue report forms provided by Eye Bank Association of America (EBAA) member eye banks list serological testing results for these viruses, the EBAA Policy and Position Review Subcommittee (PPRS) sought to investigate and clarify the implications of these results.

Methods: Current EBAA policies regarding HTLV, CMV, and EBV were reviewed. Additionally, a search of articles written in or translated into the English language regarding the aforementioned viruses with a focus on ocular infection and ocular tissue transplantation was performed on PubMed.

Results: Current EBAA policies indicate that ocular tissues from donors with seropositivity to HTLV, CMV, and/or EBV can be used for transplantation. The risk of transmission of HTLV was felt to be the most consequential, given its low seroprevalence and its association with adult T-cell lymphoma/leukemia. However, as corneal and limbal tissue are not leukocyte-rich, the risk of transmitting HTLV is low. Despite reports of the isolation of all 3 viruses in ocular tissues, a literature review did not reveal any reported cases of viral transmission through ocular tissue transplantation.

Conclusions: Ocular tissues from donors with seropositivity to HTLV, CMV, and/or EBV can be used for transplantation per current EBAA guidelines. Despite the potential for ocular infection by these viruses, there are no reported cases of viral transmission from ocular tissue transplantation, affirming the validity of the current EBAA guidelines.

Purpose: To report a case of Epstein-Barr virus (EBV) corneal endotheliitis and uveitis in a patient diagnosed with extranodal natural killer/T-cell lymphoma (ENKTL).

Methods: This is a case report performed at a tertiary care center in the Republic of Korea.

Results: A 64-year-old man presented with decreased vision in his right eye that had persisted for 4 days. Best-corrected visual acuity was finger counting at 50 cm in the right eye and 0.8 in the left eye. Intraocular pressure was within the normal range in both eyes. Slit-lamp examination revealed scattered keratic precipitations and diffuse corneal edema in the right eye. Because of the severe edema, anterior chamber (AC) details were obscured. In the left eye, +2 inflammatory cells were observed in the AC and +1 cells in the vitreous. A multiplex polymerase chain reaction test using aqueous humor samples from each eye yielded positive results for EBV but negative results for other herpes viruses. One week after initiating treatment with a topical acyclovir ointment, topical steroids, and oral acyclovir, corneal edema and AC inflammation improved. Subsequently, the patient was diagnosed with nasal ENKTL and underwent 3 chemotherapy cycles in the hematology-oncology department. Five months after commencing topical and oral antiviral therapies, best-corrected visual acuities improved to 0.5 in the right eye and 1.0 in the left eye.

Conclusions: EBV infection can cause severe corneal edema and uveitis. In patients with ENKTL, EBV should be considered a possible etiology of ocular involvement, and timely ophthalmic management may contribute to better visual outcomes.

Purpose: The objective of this study was to compare the clinical outcomes of intrastromal keratoplasty using biosynthetic corneas with human donor corneas in cases of advanced keratoconus.

Methods: A prospective nonblinded randomized controlled study was conducted at a tertiary eye center in India. Treatment-naïve patients with advanced keratoconus aged 18 years or older were included. Twenty eyes were randomized into 2 groups-group 1 (human donor corneal lenticule, n = 10) and group 2 (biosynthetic corneal lenticule, n = 10). Efficacy analyses included an increase in the thinnest pachymetry and a decrease in the maximum keratometry (Kmax). Safety analyses included any adverse events in the postoperative period.

Results: At 6 months postoperatively, the rise in the thinnest pachymetry in group 1 was 346.8 ± 40.82 to 486.7 ± 15.7 μm ( P < 0.001) and in group 2 was 366.2 ± 31.3 to 548.3 ± 59.1 μm ( P < 0.001). The biosynthetic group exhibited a significant increase in the thinnest pachymetry ( P = 0.005). However, both groups showed a similar decrease in Kmax (71.06 ± 7.95 to 63.3 ± 3.74 D in group 1 and 69.13 ± 8.54 to 61.5 ± 6.2 D in group 2; P = 0.44). No adverse events were seen at 6 months of follow-up.

Conclusion: Femtosecond-assisted intrastromal implantation of biosynthetic corneas is a safe and effective alternative to human donor corneas in cases of advanced keratoconus.

Purpose: The aim of this study was to evaluate the trends in antibiotic resistance among Pseudomonas aeruginosa isolates from microbial keratitis cases over a 9-year period.

Methods: This retrospective observational study included 154 patients with culture-proven Pseudomonas aeruginosa keratitis seen between 2014 and 2022. Antibiotic susceptibility data were reviewed for fluoroquinolones, cephalosporins, beta-lactams, aminoglycosides, and other antibiotic groups. Year-wise resistance patterns were analyzed using the chi-square or Fisher exact test. Cross-sensitivity and cross-resistance between ciprofloxacin and other fluoroquinolones were also assessed.

Results: Ciprofloxacin and other older-generation fluoroquinolones maintained high sensitivity (>85%) throughout the study. Moxifloxacin showed a higher resistance rate (23%), with a rising trend from 2014 (16%) to 2022 (36%), although there was a rise and dip in between. Cephalosporins showed poor efficacy, except for ceftazidime, which had a notably lower resistance rate (21%). Beta-lactam resistance was high, except for piperacillin-tazobactam. Aminoglycosides (gentamicin, tobramycin, and amikacin) exhibited the lowest resistance rates (<10%). Cross-resistance between ciprofloxacin and other fluoroquinolones was high, especially with ofloxacin and gatifloxacin.

Conclusions: Over 9 years, Pseudomonas aeruginosa isolates retained sensitivity to older fluoroquinolones and aminoglycosides, while there was a trend toward increasing resistance to moxifloxacin. Cephalosporin and beta-lactam resistance remained high, except for ceftazidime and piperacillin-tazobactam. Despite the limitations of the study, these findings support a continued role for ciprofloxacin and aminoglycosides as empiric therapy options.

Purpose: To develop and validate an artificial intelligence (AI)-enabled eye rubbing detection tool using sensor data collected from wrist-based wearable devices.

Methods: An automated system was designed to detect eye rubbing using wrist-based wearable devices. The system involves 3 components: sensor data acquisition, data preprocessing, and deep learning-based classification model. Six different deep learning architectures were developed, including 1D and 2D CNN-LSTM models and an ensemble, to identify the most effective approach. Two datasets were established in the time and frequency domains: a timeseries dataset contains 8640 recordings and a scalogram dataset 15 comprising 112,320 images from 20 subjects.

Results: The proposed system demonstrated strong performance, achieving an F1-score of 95.27 ± 0.87% and AUC of 98.26 ± 0.92% across 5 cross-validation folds when using the 1D CNN-LSTM model to distinguish eye rubbing and noneye rubbing activities. When evaluated on the testing set, the system maintained high performance, with an F1-score of 92.54% and AUC of 96.70%. Model inference required 15.32 milliseconds per segment, supporting real-time operation and practical deployments.

Conclusions: The proposed system provides high reliability in detecting eye rubbing behaviors, indicating its potential as a tool to support ophthalmologists and researchers in the rigorous study of the contributions of eye rubbing to the development and progression of keratoconus and other corneal ectasias.

Purpose: To evaluate the safety of magnetic resonance imaging (MRI) in patients who have previously undergone keratopigmentation, with particular attention to the potential adverse effects associated with different types of tattoo inks.

Methods: Various colored and black tattoo inks were tested under MRI conditions. In vitro analysis was conducted to assess ink mobility. Ex vivo porcine and rabbit eyes were used to evaluate macroscopic changes, MRI artifact formation, and histological modifications after exposure to the magnetic field.

Results: No adverse effects or visible artifacts were observed with iron oxide-free inks during MRI. In contrast, inks containing iron oxide produced artifacts that significantly inhibited eye analysis without affecting posterior structures. Under normal MRI conditions, histological examination revealed subtle pigment migration with iron oxide-based inks; a finding not observed with other ink types. Under supranormal exposure, pigment migration was pronounced, readily visible both macroscopically and histologically.

Conclusions: MRI appears safe in patients with keratopigmentation using iron oxide-free inks, which are the most commonly used. In contrast, iron oxide-containing inks can induce MRI artifacts that inhibit ocular assessment without affecting brain visualization. Under the influence of the magnetic field, their pigments may also migrate, potentially causing ocular pain, central corneal involvement, or weakening of corneal biomechanical integrity. For corneal tattooing, we recommend using carbon-based inks for black pigmentation and one of the iron oxide-free inks for colored keratopigmentation.

Purpose: To describe a modified long corneal tunnel technique and report preliminary observations regarding wound sealing during cultured human corneal endothelial cell (cHCEC; Vyznova) injection therapy in a small consecutive case series.

Methods: Ten consecutive eyes with bullous keratopathy underwent cHCEC injection by a single experienced surgeon using a long, tangential corneal tunnel created with a 26-gauge needle. Tunnel dimensions and injection parameters were measured retrospectively from surgical video recordings. Wound integrity was assessed intraoperatively using a dry microsponge to detect macroscopically visible fluid egress. Early postoperative anterior segment OCT (CASIA2) parameters-keratometric cylinder (ΔCyl) and endothelial anterior chamber depth (ΔACD)-were also evaluated.

Results: All eyes demonstrated macroscopically leak-free wound closure without sutures. The mean tunnel length was 4.2 ± 0.6 mm, tunnel creation time 14.9 ± 6.3 seconds, and injection time 17.2 ± 7.1 seconds. No intraoperative complications such as hypotony, wound leak, or anterior chamber collapse were observed. Postoperative fluorescein Seidel testing on day 1 confirmed absence of wound leakage in all eyes. Early postoperative OCT measurements showed no clinically meaningful change in keratometric astigmatism (ΔCyl = 0.20 ± 0.53 D), whereas endothelial ACD increased slightly (ΔACD = 0.18 ± 0.17 mm), with no eyes exhibiting anterior chamber shallowing.

Conclusions: This preliminary single-surgeon case series suggests that the long corneal tunnel technique may facilitate macroscopically leak-free wound closure during cHCEC injection. Although encouraging, these findings are limited by subjective leak assessment and small sample size. Larger multicenter studies incorporating objective leak quantification are required to determine reproducibility and comparative performance.

Purpose: The aim of this study was to identify factors associated with significant postoperative stromal thinning in eyes undergoing Descemet membrane endothelial keratoplasty (DMEK).

Methods: This was a retrospective, multicenter interventional study. Eyes that underwent DMEK at Royal Liverpool University Hospital (UK) and ASST Spedali Civili di Brescia (Italy) were included. Eyes were stratified into 2 groups based on the final central corneal thickness (CCT): <500 μm and ≥500 μm. Demographic, clinical, and tomographic parameters were analyzed, including age, preoperative CCT, best corrected visual acuity (BCVA), posterior and total corneal power, and donor endothelial cell density (ECD). Hyperopic shift was defined as an increase of ≥+0.5 D in posterior corneal power or a decrease of ≤-1.0 D in total corneal power.

Results: Among 150 eyes (120 patients), those with a final CCT <500 μm were significantly older (mean [SD], 74.5 [9.9] vs. 68.7 [11.5] years; P = 0.001). Hyperopic shift occurred in 43% of eyes with complete tomographic data and correlated with a greater percentage reduction in CCT after DMEK (-25.5% [15.6%] vs. -16.4% [12.4%], P = 0.02). A larger proportional CCT reduction was observed in eyes with a final CCT <500 μm and was associated with the presence of preoperative posterior stromal ripples. No significant differences were observed in final BCVA, donor ECD, or treatment center.

Conclusions: Greater reductions in corneal thickness are associated with postoperative stromal thinning and hyperopic shift after DMEK. Preoperative stromal ripples are associated with greater reductions in corneal thickness after DMEK. Stromal remodeling appears influenced by endothelial recovery and preoperative biomechanical status, supporting emerging hypotheses on keratocyte loss and osmotic imbalance.

Purpose: The aim of this study was to compare the efficacy and outcomes of cultivated oral mucosal epithelial transplantation (COMET) in limbal stem cell deficiency (LSCD) between patients with Stevens-Johnson syndrome (SJS) and those with other etiologies (non-SJS), evaluated by clinical manifestations and epithelial phenotypes.

Methods: This prospective, comparative study enrolled patients with LSCD who were scheduled for COMET. Preoperative and postoperative assessments were performed using slit-lamp microscopy, in vivo confocal microscopy (IVCM), and impression cytology with immunofluorescence staining. Successful outcomes were defined as an intact ocular surface without conjunctivalization and the presence of cornea-like epithelium detected by IVCM and/or immunofluorescence staining at the central cornea. Otherwise, the outcomes were interpreted as failure. Visual improvement and risk factors of COMET failure were analyzed.

Results: Eighteen eyes of 18 patients (7 with SJS, 11 non-SJS) were included. The median follow-up time was 15.5 months (range: 13-35 months). The overall success rate was 72.2% (13 eyes: 2 with SJS and 11 non-SJS), which was significantly lower in patients with SJS (28.6%) than in non-SJS patients (100%) (P = 0.002). Among successful cases, 60.2% showed visual improvement while the others (30.8%) remained unchanged. The risk of COMET failure was significantly associated with SJS (P = 0.002), lid margin keratinization (P = 0.023), preoperative symblepharon (P = 0.036), postoperative epithelial defects lasting more than 2 weeks (P = 0.022), and the absence of multilayered cornea-like epithelium detected by IVCM at 6 months postoperatively (P = 0.017).

Conclusions: COMET demonstrates good efficacy and favorable outcomes for LSCD, particularly in non-SJS eyes. While the success rate was excellent in non-SJS patients, the outcomes were significantly limited in those with SJS.